What does AL stand for in the project? It should be a beam, but I don't know the details. Please help, thank you.

dark beam.

the concealed beam is used in the position where it is not allowed to set beams or shear wall corner windows between frame columns, so as to pull through the frame and make the structural system as reasonable as possible, and there are walls on the board, while the building is not allowed to leak beams under the board (or turn over beams), so it is to set concealed beams.

one kind of concealed beam is designed according to the stress state, at this time, it should be reinforced according to the calculation mode and calculation diagram, and the other is treated according to the structure, which is a means to embody the conceptual design and a measure to strengthen the rigidity and integrity or make the stress more reasonable.

The cross-section height of the concealed beam is the same as the thickness of the slab, and the width can be determined according to the actual needs. The concealed beam can be set without stirrups and shear resistance, and there is no need to set negative bending reinforcement on the concealed beam, because the rigidity of the concealed beam can not play the role of bearing for the cast-in-place slab.

Extended information:

Safety precautions on the construction site:

1. Safety propaganda slogans and construction safety signs should be set up on the construction site, and other personnel are not allowed to dismantle them without authorization. If the safety signs are damaged, they should be replaced and reset in time.

2. There should be safety guardrails at the edges of ditches, pits and ponds in the construction site, and there should be special personnel to direct traffic when working in a narrow corner construction site.

3. attention should be paid to fire prevention, flood control, wind prevention, explosion prevention and shock prevention in the construction site.

4. Safety protection measures shall be provided in the dangerous areas of high slopes and foundation pits excavated on the construction site.

Baidu Encyclopedia-Dark Beam

Baidu Encyclopedia-Shear Wall

Baidu Encyclopedia-Reinforcement

Baidu Encyclopedia-Effective Height of Section